[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

RE: Phase 4 satellite(s)?



> My involvement in AMSAT to date has mostly been contributing $$$ since
> until recently, I had no opportunity to install antennas to work the
> existing satellites.  So, I have no "legacy" mode to be compatible
> with.

I do have a small amount of "legacy gear", but my investment has been modest
and the equipment serves other purposes as well, as I don't have elevation
rotators or other satellite specific hardware.

> What I find remarkable is that people seem to be willing to invest a 
> bunch of money on antennas, feedline, Az/El rotators, amplifiers,
> pre-amps, polarity switchers and probably a bunch of other satellite
> operation specific hardware.  Yet, investing in a computer (which
> they probably already have) and a sound card or an external modem
> for a new type of modulation somehow sets the bar too high.

Maybe it's the old known versus the unknown issue.  I'm actually the
opposite.  Building a new rig may cost a bit of money and time (and I don't
have a lot of the latter!), but it's something I _can_ do (and a nice, meaty
technical challenge).  OTOH, permanent antenna installations are out of the
question, due to space/ownership restrictions.  For me, the bar is much
higher for AO-10 than for Phil's proposed LEO constellation.  AO-40 is also
likely to be workable, provided I stick to L/S and above (I've written V/U
off for anything other than near perigee passes - assuming AO-40 still works
on these bands).

> Packet radio and AX.25 were pretty radical when it was introduced,
> yet it seems rather commonplace and pedestrian now.  The growing
> popularity of things like PSK31 for "RTTY-like" applications seem
> to have no huge barrier to implementation.  But carrying voice
> by other than SSB.. that's a different matter.  

The difference here is that the "RTTY-like" modes need no extra hardware
(besides the odd cable), assuming one has a Pentium class PC in the shack,
which is pretty common these days, especially since many would have put the
PC in for packet some years ago.  However, digital voice will require extra
hardware, basically a whole new transceiver, one which can't (at least
initially) be bought off the shelf.  Perhaps we're too used to being able to
throw money at our problems and have those nice folks at Icom, Kenwwo,
Yaesu, Alinco or other places hand us the solution.  All of a sudden, we
actually have to _build_ our gear again!  If you ask me, that's a good
thing, if we can get enough people to do it (count me in!).

> Sure, it's *different*.  And perhaps these new "modes" don't
> support quaint notions like "pile-ups" when trying to work that
> elusive DX station. For those that are competative, perhaps new
> contests would be more appropriate (e.g., fasted file transfer rate?
> Highest fidelity sound/hz of bw?) that would help drive the
> development of new techniques, rather than just the same old
> thing.

Yes, perhaps there will be new forms of contesting.  Digital modes will have
their challenges, and won't always offer 100% voice quality (I certainly
remember some grotty GSM phone calls, especially in the early days of GSM
here ;) ).  There will be technical challenges in tweaking the system
(minimum bandwidth simultaneous voice and data, perhaps video compression).
Oh, and foxhunting a digital transmitter.  That _could_ be an interesting
twist to the old sport. :-)

> 
> louie
> wa3ymh
> 
> 
> 
> 
> 
> ----
> Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
> 
----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home